IgE to wheat, prick test, and Patch test among children with celiac disease

Introduction and aim Celiac disease is one of the most common autoimmune disorders. This study aimed to evaluate the relationship between celiac disease and wheat sensitization. Subjects and methods In the current study, children aged < 18 years with confirmed celiac disease were included. Data were analyzed using SPSS. Results Gastrointestinal problems were the most common indication for evaluation in terms of celiac disease. Prick and patch tests were positive in 43.4% and 34% respectively. Conclusion Prick test and patch test for wheat sensitization were positive in about 30–45% of the children for celiac disease.


Introduction and aim
Celiac disease is an immune enteropathy caused by gluten ingestion.Prevalence of celiac disease was increased [1].Intestinal and extraintestinal presentation of celiac disease were reported.There are few case reports about the co-existence of celiac disease and wheat allergy [2,3]-the current study aimed to evaluate a possible association between celiac disease and wheat sensitization.taped to the patient's back.After a few days, cases were assessed for reading of patch test.All participants were informed about the details of testing with the manual of testing in the local language.
Diagnosis using pathology was included in the current study.Marsh classification was used to diagnose celiac disease.IgE reaction with gluten was evaluated using the CAP method [7].Age, sex, symptoms, prick, and patch test were analyzed.Correlations were done using Chisquare.SPSS ver was used for analysis.A T-test was used for the Mean with normal distribution.Mann-Whitney was used for the Mean with abnormal distribution.P value < 0.05 was considered significant.

Results
In the current study, 53 (m = 20, f = 33) cases were included ( Table 1).The most common reason for the investigation was gastrointestinal complaints (75.5%) followed by growth retardation (17%).The most common complaint among gastrointestinal problems was stomachache (Table 1).The most common grade was 3b in 71.7% of children.Prick tests and patch tests were positive in 43.4% and 34% of the patients with celiac disease( Table 1).Anemia was the most commonly associated symptom (Table 1).Of the cases, one case had respiratory problems.Diarrhea was seen in 12(22.6%);nausea in 3(5.7%); stomachache in 17(32.1%);constipation in  2.
As seen in Table 3, there is no significant correlation between patch test response and age at diagnosis( p = 0.35), total IgE level (p = 0.517), eosinophil count (p = 0.39), and anti-TTG level(p = 0.846).No significant correlation was seen between prick test response, eosinophil count, tissue transglutaminase level, and IgE to wheat( p > 0.05).

Discussion
In our study, prick, and patch tests for wheat sensitization were positive in 43.4% and 34%, respectively.In another study by Jafari et al., among 44 patients with celiac disease, 22 had at least one positive skin prick test for food allergen [8].Wheat allergy was seen in 18.2% of the children with celiac disease in their study [8].In another study from Brazil, wheat allergy was seen in 4% of children with celiac disease [9].Other studies reported 8.3-11.9% of wheat allergies among children with Celiac disease [10][11][12].
In a systematic review, authors recommended screening of allergies in patients who have symptoms after introducing a gluten-free diet [13].Wheat allergy is the most common allergy among patients with CD, especially in children [14].Wong et al. reported a girl with CD and IgE-mediated wheat allergy [15].The positive association between celiac disease and IgE sensitization to some food was also reported [16].In the study by Spoerl et al., a positive association between celiac disease and wheat allergy was not found [17].
It seems that the frequency of wheat sensitization in children with celiac disease in our country was higher than in other studies.Anemia was seen in 18.9% of the children.In another study, iron deficiency anemia was seen in 30% of children with celiac disease [18].
As mentioned above, the frequency of wheat sensitization was higher than in other reports, and this may be due to differences in ethnicity and type of evaluation.However, due to the high frequency of wheat allergy in our community, other studies are recommended.

Limitation
Single-center study and lack of local data for wheat sensitization in our geographic location.

Conclusion
The frequency of wheat sensitization among children with celiac disease was higher than in other studies.More studies are recommended.

Table 1
Demographic and clinical manifestation and complication among children

Table 2
Laboratory findings among children with celiac disease

Table 3
Comparison between Prick test and Patch test results in terms of laboratory findings